Search for anomalous couplings in top decay at hadron colliders

Journal Article · Wed Mar 01 04:00:00 EST 2006 · Physical Review. D, Particles Fields

DOI:https://doi.org/10.1103/PhysRevD.73.054011· OSTI ID:20776858

Tsuno, S; Nakano, I; Tanaka, R; Sumino, Y ^[1]

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1. Department of Physics, Okayama University, Okayama, 700-8530 (Japan)

We present a quantitative study on sensitivities to the top-decay anomalous couplings, taking into account realistic experimental conditions expected at Tevatron and LHC. A double angular distribution of W and charged lepton in the top-decay is analyzed, using tt events in the leptons+jets channel. In order to improve sensitivities to the anomalous couplings, we apply two techniques: (i) We use a likelihood fitting method for full kinematical reconstruction of each top event. (ii) We develop a new effective spin reconstruction method for leptonically-decayed top quarks; this method does not require spin information of the antitop side. For simplicity, we neglect couplings of right-handed bottom quark as well as CP violating couplings. The 95% C.L. estimated bound on a ratio of anomalous couplings reads -0.81<f{sub 2}/f{sub 1}<-0.70, -0.12<f{sub 2}/f{sub 1}<0.14 using 1000 reconstructed top events at Tevatron, while -0.74<f{sub 2}/f{sub 1}<-0.72, -0.01<f{sub 2}/f{sub 1}<0.01 is expected with 100 k reconstructed top events at LHC, where only statistical errors are taken into account. A two-fold ambiguity in the allowed range remains when the number of events exceeds a few hundred.

• OSTI ID: 20776858
• Journal Information: Physical Review. D, Particles Fields, Journal Name: Physical Review. D, Particles Fields Journal Issue: 5 Vol. 73; ISSN PRVDAQ; ISSN 0556-2821
• Country of Publication: United States
• Language: English

Related Subjects

72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS
ANGULAR DISTRIBUTION
B QUARKS
CERN LHC
FERMILAB TEVATRON
HADRONS
INCLUSIVE INTERACTIONS
INTERMEDIATE BOSONS
JET MODEL
LEPTONIC DECAY
LEPTONS
PARTICLE PRODUCTION
PROTON-PROTON INTERACTIONS
SENSITIVITY
SPIN
T QUARKS